DESCRIPTION: The long-term research goal is development of a simplified magnetic cell selection system. Cell selection is important in research, diagnosis, and therapy. Magnetic cell selection is often the method of choice for the isolation of pure cell populations, such as stem cells, or for the removal of specific cells, such as lymphoma cells. A simplified system would make magnetic cell selection more convenient and more widely used. The key to simplification of the system is the use of better magnetic particles. A new type of magnetic particle will be prepared which will be easily separated using magnets, but will remain in stable colloidal suspension and react rapidly with cells. The particles will have a novel solid magnetic core. The magnetic core will be coated with a hydrophilic gel and labeled with binding proteins. The hydrophilic gel will prevent non-specific binding of particles to cells and will provide the binding proteins the mobility required for efficient specific binding to the target cells. The proposed research will focus on developing and evaluating methods for the preparation of the solid magnetic cores and on chemical modification of the hydrophilic gel. PROPOSED COMMERCIAL APPLICATION: The new magnetic particles can be used for disease diagnosis, stem cell isolation, and in vitro diagnostics, all of which are commercially important activities, as well as being medically important.